Methods and apparatus for fabricating, handling and transporting elongate bags of material

ABSTRACT

A material handling method (and corresponding apparatus) packages material (such as loose-fill thermal insulation product) into elongate bags, and automatically arranges the elongate bags into groups, wherein at least one group has a cross-stacked configuration. The bag groups are automatically lifted and transported, group by group, to form a multi-row stack of elongate bags whose bottom row is realized by a cross-stacked group. The multi-row stack is transported to a customer. The elongate bags preferably each have dimensions of about 38″ by 21″ by 8.5″ and carry about 27 lbs. of product. Preferably, a modified clamp truck is used to lift and transport the bag groups. The clamp truck has two clamp members that translate relative to one another with one clamp member having a central support bar integral thereto and laterally disposed between said two clamp members. The central support bar fits into a slot in a conveyor belt system to facilitate positioning the two clamps members around a cross-stacked bag group supported by the conveyor belt system.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates broadly to methods and apparatus for fabricating,handling and transporting elongate bags of material, such as loose-fillthermal insulation.

2. State of the Art

In recent years, the use of blowable (or pourable) loose-fill thermalinsulation products has increased in popularity because it can be easilyand quickly applied in both new construction as well as in existingstructures. The loose-fill thermal insulation product may be made ofglass-fiber material, such as the Insulsafe® brand commerciallyavailable from Certainteed Corporation of Valley Forge, Pa.Alternatively, the loose-fill insulation product may be made ofcellulose material.

The loose-fill thermal insulation product is typically packaged inelongate bags at the factory for distribution therefrom. For blown-inapplications, the loose-fill insulation product is installed by addingthe product to the hopper of a pneumatic blower which blows theinsulation into the desired area under control of a human operator. Forpour-in applications, the loose-fill insulation product is removed fromits bag and poured into the desired area by hand.

Prior to transport from the factory, the bags of loose-fill thermalinsulation product are arranged in rows stacked upon one another. Ingeneral, the finished stacks are handled by clamp trucks (for example,moving the stacks from the end of the production line to a warehouse orto transport trucks). The parallel stacking pattern is used normally onthe bottom layer of bags in each stack so that the clamp truck can pickup the stack without dropping bags. In this configuration, thelongitudinal dimensions of the bags are aligned in the same directionand the clamp truck clamps the stack such that the closing force of theclamps are parallel to the longitudinal axis of the stacked bags asshown in FIG. 1A.

If the clamp truck were to attempt to pick up a stack whose bottom layerwas cross-stacked as shown in FIG. 1B, the majority of the clampingforce would be transmitted perpendicular to the longitudinal axis of twoof the cross-stacked bags as shown. In this configuration, once thestack is lifted, gravity pulls the bags downward. Because the two bagslack a friction force to keep from sliding past one another, they tendto roll out of the bottom of the clamps as shown in FIG. 1C, whichcauses the entire stack to fall over and result in undue delays inhandling the bags.

Although the parallel-stacked configuration is suitable for handling bya clamp truck, it is not suitable when used for the bottom row of astack that is to be picked up by a fork lift, which is used by mostcustomers (e.g., retailers, contractors, distributors, installers) tohandle the stacks. Therefore, before the stack is loaded onto atransport truck, the bottom parallel-stacked row is typically manuallyarranged in a cross-stacked configuration. In this manner, the customercan readily unload the stack with a fork lift.

Such manual arrangement of the thermal insulation bags for transport tocustomers is labor intensive and thus costly to implement. Thus, thereremains a need in the art to provide for improved methods and systemsfor the arrangement of loose-fill thermal insulation bags for transportto customers, wherein the arrangement is carried out in a manner that isless manually intensive and thus less costly than the prior art methods.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide improved materialhandling methods and systems for the automatic (e.g., machine-based)arrangement of loose-fill thermal insulation bags in a manner suitablefor transport to and by customers (such as retailers, contractors,distributors, installers).

It is another object of the invention to provide material handlingapparatus that can be used to realize such methods.

In accord with these objects, which will be discussed in detail below, amaterial handling method (and corresponding system) packages material(such as loose-fill thermal insulation product) into elongate bags, andautomatically arranges the elongate bags into groups, wherein at leastone group has a cross-stacked configuration. The bag groups areautomatically lifted and transported to form a multi-row stack ofelongate bags whose bottom row is realized by a cross-stacked group. Themulti-row stack is transported to a customer. The elongate bagspreferably each have dimensions of about 38″ by 21″ by 8.5″ and carryabout 27 lbs. of product.

It will be appreciated that such material handling methodology (andsystems based thereon) avoids manual arrangement of the elongate bags ofthermal insulation product and thus provides valuable cost savings tothe manufacturer.

According to one embodiment of the invention, a stacker machineautomatically lifts and transports groups of elongate bags to form themulti-row stack. The stacker machine has a moveable stacker head withfingers that grip a given group of elongate bags and at least onesupport structure that is operably disposed between the bags disposedside-by-side in the cross-stacked configuration to provide a frictionfit therebetween.

According to another embodiment of the invention, a modified clamp truckis used to lift and transport the bag groups. The clamp truck has twoclamp members that translate relative to one another with one clampmember having a central support bar integral thereto and laterallydisposed between the two clamp members. The central support bar fitsinto a slot in a conveyor belt system to facilitate positioning the twoclamp members around a cross-stacked bag group supported by the conveyorbelt system.

Additional objects and advantages of the invention will become apparentto those skilled in the art upon reference to the detailed descriptiontaken in conjunction with the provided figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic illustration of the clamp force applied to aparallel-stacked row of elongate bags of loose-fill thermal insulationproduct.

FIG. 1B is a schematic illustration of the clamp force applied to across-stacked row of elongate bags of loose-fill thermal insulationproduct.

FIG. 1C is a schematic illustration of the bag roll that results fromthe application of the clamp force to the cross-stacked row shown inFIG. 1B.

FIG. 2 is a flow chart illustrating the methodology of fabricating,handling, and transporting elongate bags of loose-fill thermalinsulation product in accordance with the present invention.

FIG. 3 is a partial perspective view of a stacker machine that forms amulti-row stack of elongate bags of loose-fill thermal insulationproduct in accordance with the present invention.

FIG. 4 is a cut away perspective view of a conveyor assembly thatsupports a multi-row stack of elongate bags of loose-fill thermalinsulation product in accordance with the present invention.

FIG. 5A is a perspective view of a clamp mechanism that is used as partof clamp truck for loading and lifting the multi-row stack of FIG. 4 inaccordance with the present invention.

FIG. 5B is a side view of the clamp mechanism of FIG. 5A.

FIG. 6 is a cut away perspective view of a conveyor belt system thatincludes a slot that accepts the central support flange of the clampmechanism of FIGS. 5A and 5B to thereby facilitate loading and liftingof the multi-row stacks of loose-fill thermal insulation product fromthe conveyor belt system in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to FIG. 2, there is shown a flow chart illustrating themethodology for fabricating, handling and transporting elongate bags ofloose-fill thermal insulation in accordance with the present invention.The methodology begins in block B10 by fabricating blowable (orpourable) loose-fill thermal insulation product. The details of anexemplary method for fabricating the blowable (or pourable) loose-fillthermal insulation product is described in detail in U.S. Pat. No.5,683,810 Babbitt et al., herein incorporated by reference in itsentirety. In this system, glass fibers are produced by a fiberizerassembly from molten glass supplied by a furnace. The glass fibers arecollected to form a fibrous blanket that is cut into nodules by anin-line chopping device. A dust-suppressant/anti-static agent is appliedto the nodules.

In block B20, the loose-fill thermal insulation product is collected andpackaged into elongate bags. Machinery for packaging the loose-fillthermal insulation product is well known in the art. For example, seeU.S. Pat. Nos. 4,716,712 and 4,640,082, herein incorporated by referencein their entirety. The elongate bags generally have an elongate shapewhose maximum length is substantially greater than its maximum width.The elongate bags may have dimensions of about 38″ by 21″ by 8.5″ andcarry about 27 lbs. of product. Such dimensions and weight enable thebags to be carried into attics and crawlspaces. It should be appreciatedthat the dimensions and weight of the bag may vary as desired. The bagspreferably comprise a suitable polymer (such as polyethylene) which isflexible and water resistant yet provides adequate structural support tohold the product during transport.

In block B30, the bags are automatically arranged into groups eachhaving either a parallel-stacked configuration or a cross-stackedconfiguration. In the parallel-stacked configuration, the longitudinaldimensions of the bags are aligned along the same direction as shown inFIG. 1A. In the cross-stacked configuration, a first set of bags (201A,201B) are disposed side-by-side along their lengths, and one or moreadditional bags (203) are disposed orthogonal to and adjacent thesefirst set of bags as shown in FIGS. 3 and 4. In this configuration, thelengths of the first set of bags (201A, 201B) are substantially alignedalong a first direction (e.g., y-direction) and the length(s) of the oneor more additional bags (203) are aligned along a second direction(e.g., x-direction) that is orthogonal to the first direction as shown.Preferably, the desired bag pattern (either parallel-stacked orcross-stacked) is arranged by a series of rollers and mechanicaldiverters. The selection of the desired bag pattern is preferablycontrollable via software (or other programming mechanism) as is wellknown in the material handling arts.

In block B40, a stacker machine automatically lifts the bag groupsarranged in block B30 to form a multi-row stack of bags. Preferably, themulti-row stack contains at least thirteen layers of three-bag rows fora total of 39 elongate bags per stack. The bottom row of the multi-rowstack has a cross-stacked pattern. The rows above the bottom row mayhave a parallel stacked pattern or a cross-stacked pattern. An exemplarystacker machine is shown in FIG. 3. Each bag group is arranged in astaging area 301 in the desired pattern (either cross-stacked orparallel-stacked). Once the bags are arranged in the desired pattern, astacking head 303 lowers and grips the bag group with its fingers 305A,305B, 305C, 305D in a manner similar to that shown in FIG. 1A for theparallel-stacked configuration and shown in FIG. 1B for thecross-stacked configuration. The problem of roll-out with respect to thecross-stacked pattern (discussed above with respect to FIG. 1B and 1C)is remedied by the presence of small chains 307A, 307B that are locatedto fit between the two lengthwise bags of the cross-stacked pattern whenthe stacker head 303 is lowered down. The chains 307A, 307B aresandwiched between the two lengthwise bags when the fingers 305A, 305B,305C, 305D clamp shut to provide a friction fit therebetween thatprevents the two lengthwise bags from slipping past one another. Thechains may be readily substituted with wire strands, rope strands orother support structures that fit between the lengthwise bags andprevent such bags from slipping past one another. After gripping the baggroup, the stacking machine automatically lifts the bag group and movesit onto the top of the multi-row stack that it is building. Typically,the multi-row stack is built at a location adjacent the staging area.This process is repeated for each row of the multi-row stack.Preferably, the operations of the stacker machine are automated viasoftware-based control systems (or other programming mechanisms) as arewell known in the material handling arts.

After the formation of the multi-row stack is complete, the multi-rowstack is lifted for transport (for example, to a warehouse or to atransport truck) in block B50. Advantageously, the cross-stack bagarrangement of the bottom row of the multi-row stack is suitable forunloading with a fork lift. Preferably, the stack is transported by aconveyor system to an area where it is picked up by a clamp truck. InFIG. 4, the end of the conveyor system is shown with a multi-row stackdisposed thereon. The clamp truck has two pinching clamp members 501,503 as shown in FIG. 5A. An exemplary clamp truck is described in detailin U.S. Pat. No. 3,971,584 Duncan, herein incorporated by reference inits entirety. The two clamp members 501, 503 translate relative to oneanother, preferably under hydraulic control, to grasp the elongate baggroup positioned therebetween. One of clamp members (for example, theclamp member 501) has a central support bar 505 integral thereto asshown in FIGS. 5A and 5B. The central support bar 505 is preferably aflat bar four inches to six inches wide that is welded to a bottom edgeof one of the clamp members such that it is fixed to a lateral positionmidway between the two clamp members. The central support bar 505extends below the major clamping surfaces of the clamping members andfits into a slot 603 in the conveyor belt system 601 as shown in FIG. 6to facilitate positioning the clamps members 501, 503 around a bag groupsupported by the conveyor belt system for loading and lifting of the baggroup therefrom. Preferably, the slot 603 is formed by a void betweentwo traction belt drives 605B and 605C as shown. The traction beltdrives 605A, 605B, 605C, 605D extend the conveyor belt system 601. Inthis configuration, the central support bar 505 rests under the centralregion of the bag(s) of the cross-stacked arrangement that are alignedorthogonal thereto to provide support to these bag(s) when thecross-stacked bag group is grasped and lifted by the pinching andlifting motion of the clamp members 501, 503 of the clamp truck.

There have been described and illustrated herein several embodiments ofa method and corresponding apparatus for handling elongate bags ofloose-fill thermal insulation product. While particular embodiments ofthe invention have been described, it is not intended that the inventionbe limited thereto, as it is intended that the invention be as broad inscope as the art will allow and that the specification be read likewise.Thus, while particular material arrangements and configurations havebeen disclosed, it will be understood that other configurations can beused. Furthermore, while particular methodologies and correspondingapparatus have been disclosed for loose-fill thermal insulation product,it will be appreciated that such methods and apparatus can be readilyapplied to other products packaged in elongate bags. Moreover, whileparticular machine configurations have been disclosed, it will beappreciated that other machine configurations could be used as well. Forexample, and not by way of limitation, the central support bar may beaffixed to one of the clamping members by non-rigid means to enableslidable movement of the central support bar relative to the oneclamping member. This feature may be advantageous because it allows thecorresponding slot in the conveyor system to be narrower (it is nolonger constrained by the amount of travel required for grasping a baggroup) and thus provides for improved support of the bag group. It willtherefore be appreciated by those skilled in the art that yet othermodifications could be made to the provided invention without deviatingfrom its spirit and scope as claimed.

1. In a lift truck, an improvement comprising: two clamp members thattranslate relative to one another to grasp and lift material positionedtherebetween, wherein one of said two clamp members has a centralsupport bar integral thereto and laterally disposed between said twoclamp members.
 2. A lift truck according to claim 1, wherein: saidcentral support bar is adapted to fit into a slot in a conveyor beltsystem to thereby facilitate positioning the two clamps members aroundmaterial disposed therebetween and supported by the conveyor beltsystem.
 3. A method of handling material comprising: packaging materialinto elongate bags; automatically arranging the elongate bags intogroups, wherein at least one group has a cross-stacked configuration;and automatically lifting and transporting said groups of elongate bags,group by group, to form a multi-row stack of elongate bags whose bottomrow comprises a group having a cross-stacked configuration.
 4. A methodaccording to claim 3, further comprising: lifting and transporting themulti-row stack of elongate bags for transport to a customer.
 5. Amethod according to claim 3, wherein: the material comprises loose-fillthermal insulation product.
 6. A method according to claim 5, wherein:said loose-fill thermal insulation product comprises glass-fibermaterial.
 7. A method according to claim 5, wherein: said loose-fillthermal insulation product comprises cellulose material.
 8. A methodaccording to claim 5, wherein: said elongate bags each have dimensionsof about 38″ by 21″ by 8.5″ and carry about 27 lbs. of product.
 9. Amethod according to claim 3, wherein: said elongate bags comprise apolymer.
 10. A method according to claim 3, wherein: wherein each groupof elongate bags is transported by a conveyor assembly.
 11. A methodaccording to claim 3, wherein: said cross-stacked configurationcomprises two bags disposed side-by-side along their lengths and oneadditional bag disposed orthogonal to and adjacent the two bags.
 12. Amethod according to claim 3, wherein: said automatic lifting andtransporting said groups of elongate bags is carried out by a stackermachine having a moveable stacker head with fingers that grip a givengroup of elongate bags and at least one support structure that isoperably disposed between bags disposed side-by-side in saidcross-stacked configuration to prevent such bags from sliding past oneanother.
 13. A method according to claim 12, wherein: said supportstructure comprises at least one chain.
 14. A method according to claim12, wherein: said structure comprises one of wire strands and ropestrands.
 15. A method according to claim 4, wherein: said lifting andtransporting of said multi-row stack is carried out by a lift truckhaving two clamp members that translate relative to one another to graspand lift a group of elongate bags positioned therebetween, wherein oneof said two clamp members has a central support bar integral thereto andlaterally disposed between said two clamp members.
 16. A methodaccording to claim 15, wherein: said central support bar fits into aslot in a conveyor belt system to facilitate positioning the two clampsmembers around a group of elongate bags.
 17. A material handling systemmaterial comprising: means for packaging material into elongate bags;means for automatically arranging the elongate bags into groups, whereinat least one group has a cross-stacked configuration; and means forautomatically lifting and transporting said groups of elongate bags,group by group, to form a multi-row stack of elongate bags whose bottomrow comprises a group having a cross-stacked configuration.
 18. Amaterial handling system according to claim 17, wherein: the materialcomprises loose-fill thermal insulation product.
 19. A material handlingsystem according to claim 18, wherein: said loose-fill thermalinsulation product comprises glass-fiber material.
 20. A materialhandling system according to claim 18, wherein: said loose-fill thermalinsulation product comprises cellulose material.
 21. A material handlingsystem according to claim 18, wherein: said elongate bags each havedimensions of about 38″ by 21″ by 8.5″ and carry about 27 lbs. ofproduct.
 22. A material handling system according to claim 17, wherein:said elongate bags comprise a polymer.
 23. A material handling systemaccording to claim 17, wherein: wherein each group of elongate bags istransported by a conveyor assembly.
 24. A material handling systemaccording to claim 17, wherein: each group comprises two bags disposedside-by-side along their lengths and one additional bag disposedorthogonal to and adjacent the two bags.
 25. A material handling systemaccording to claim 17, wherein: said means for automatically lifting andtransporting said groups of elongate bags comprises a stacker machinehaving a moveable stacker head with fingers that grip a given group ofelongate bags and at least one support structure that is operablydisposed between bags disposed side-by-side in said cross-stackedconfiguration to prevent such bags from sliding past one another.
 26. Amaterial handling system according to claim 25, wherein: said supportstructure comprises at least one chain.
 27. A material handling systemaccording to claim 25, wherein: said structure comprises one of wirestrands and rope strands.
 28. A material handling system according toclaim 17, further comprising: a lift truck having two clamp members thattranslate relative to one another to grasp and lift a group of elongatebags positioned therebetween, wherein one of said two clamp members hasa central support bar integral thereto and laterally disposed betweensaid two clamp members.
 29. A material handling system according toclaim 28, further comprising: a conveyor belt system having a slotadapted to receive said central support bar to thereby facilitatepositioning the two clamps members around a group of elongate bagssupported by said conveyor belt system.